electron-withdrawing

Conclusions: The alkanes substituted phenolshigher antioxidant activity than that of electron-withdrawing groups substituted phenols.

结论: 烷烃基类取代物易于抗氧化,卤代烃基或硝基类取代物抗氧化活性差.

The Electron-withdrawing Effect of the Nitrogen Atom of Pyridine

吡啶环中N-原子的吸电效应

Electron-withdrawing 2-substituents electron-donating 3-substituents of the phenyl ring are favorable for increased herbicidal activity.

苯环2位是拉 电子基,3位是给电子基有利于提高除草活性.

It can be provided with some information on studying of the relationship between physical properties and chemical structure by introduction of the electron-withdrawing groups to the nitrogen of aniline.

为进一步研究在氮的位置上引入吸电子基团的聚苯胺类衍生物的物理性质与化学结构之间的关系提供了依据。

Only when the substrates with strong electron-withdrawing group were failed in this reaction.

只有当底物带有强吸电子基团，反应无法进行。

Electron-donating groups can increase the intensity of fluorescence, but the electron-withdrawing groups have opposite functions.

供电子取代基能增加卟啉的荧光强度，而吸电子取代基作用相反；